Healthy 30-Something Women Are Freezing Their Eggs Despite A Lack Of Research Behind It

Looking to press the snooze button on their biological clock, healthy, 30-something women are choosing to freeze and bank their eggs for possible future use.

Perhaps they’re not yet ready to have children—they want to focus on their career or travel. More commonly, research suggests, they haven’t yet met a partner with whom to raise a child. They might not be ready to become pregnant until they’re in their 40s, by which time the quality of their eggs will make it more difficult to conceive, even with the help of fertility treatments. Egg freezing, which also goes by the name "oocyte preservation," is a way to hedge their bets.

“I’m seeing more and more of these patients,” Dr. Janis Fox, a reproductive endocrinologist at the Brigham and Women’s Hospital and an assistant professor at Harvard Medical School, told me. Fox led a team that published a study online Monday in the journal Human Reproduction to help guide women—and their physicians—on the number of eggs they should freeze to maximize their chance of conceiving with one down the road.

"I do not know the percentage of our 3,500 annual IVF [in vitro fertilization] cycles that are for oocyte cryopreservation, but they definitely make up a significant percentage," Dr. Vinay Gunnala, a fellow at the Weill Cornell Medical College Center for Reproductive Medicine, told me in an email. Gunnala coauthored a review article on the topic in this month's issue of Current Opinion in Obstetrics and Gynecology.

Intracytoplasmic sperm injection (ICSI) of a human egg, or oocyte, appears on a TV screen. Given the current technology, ICSI must be used to fertilize eggs that have been frozen and then thawed, because that process can toughen their outer shell. (GEORGES GOBET/AFP/Getty Images)

Egg freezing isn’t new. In fact, the first baby conceived with an egg that had been frozen and then thawed was born 30 years ago.

But it was only a little more than four years ago, in October 2012, that the American Society of Reproductive Medicine (ASRM) and its affiliate, the Society for Advanced Reproductive Technology (SART), which represents virtually all U.S. clinics that perform IVF, published an updated guideline that concluded egg freezing no longer was an experimental procedure.

“The success of oocyte cryopreservation has improved dramatically over the past decade, and preliminary data for safety are reassuring,” the ASRM and SART practice committees wrote, boosting interest in egg freezing.

According to the ASRM/SART guideline, candidates for oocyte cryopreservation include:

Young women or adolescent girls undergoing chemotherapy or radiation therapy for cancer, placing them at high risk for infertility.

Women with genetic mutations that place them at a high risk of ovarian cancer, spurring them to remove their ovaries as a preventive measure before they’ve had children.

Some couples undergoing IVF. For example, they might need to freeze eggs because the man is unable to collect a semen sample to fertilize fresh eggs that have been retrieved from the woman.

However, there is “not yet sufficient data to recommend oocyte cryopreservation for the sole purpose of circumventing reproductive aging in healthy women,” according to the ASRM/SART guideline. “Marketing this technology for the purpose of deferring childbearing may give women false hope…”

Turn on the radio in the Washington, D.C., area, where I live, though, and you’re bound to hear commercials for local clinics’ egg-freezing services aimed at healthy women inching toward the end of their reproductive years.

“This is an option that women might want to consider,” Fox said. “The way I kind of think about it is it’s like insurance. If you don’t need these [frozen] eggs, great.”

That lack of data to support the effectiveness of egg freezing in healthy women is still a problem, Fox acknowledged. That's in part due to the fact that, because the option is relatively new, most healthy women who've banked their frozen eggs haven't yet tried to use them. As a result, the likelihood of them having a healthy baby with an egg they've frozen isn't known.

Female cancer patients, who could be in their teens or 20s, have no other option if they want to conceive children some day, and their youth gives them an advantage in achieving that goal with a banked egg. But, as the ASRM/SART guideline notes, healthy women most interested in egg freezing are typically in their late reproductive years, by which time egg quality might have significantly declined.

Egg freezing isn’t cheap. Most women can expect to pay up to $6,000 out-of-pocket, excluding the medications they must take to stimulate their ovaries to produce mature eggs, for one egg-freezing cycle, Fox and her coauthors wrote in their new report. (They had presented their preliminary findings in October at the annual ASRM Scientific Congress.)

It would be helpful to give women an idea of how many eggs they need to conceive a healthy baby when they decide to use them. Since few women who froze eggs in their 30s have returned to use them, Fox's team focused on another group of women undergoing IVF—those who require intracytoplasmic sperm injection (ICSI) to fertilize their eggs.

ICSI, in which a single sperm is injected into an egg, is used mainly with couples in which the man has below-average fertility. However, with the current technology, it is also required for IVF with eggs that have been frozen and thawed, because that process can toughen the shell that surrounds them, Fox said. That makes it difficult to fertilize an egg by simply placing it in a dish with sperm.

Fox's team used data from 520 healthy, fertile women undergoing IVF with ICSI at the Brigham. The cycles used fresh, not previously frozen eggs, but other studies have found that 95% of eggs frozen when women were 35 or younger survive thawing, and 85% of eggs banked when women were over 35 do, Fox said.

Besides the data about survival rates of thawed eggs, the researchers considered the proportion of eggs fertilized in the women undergoing ICSI, the women's ages and the number of healthy embryos needed to attain one live birth. According to the formula they developed, a 35-year-old woman who freezes 10 eggs after her first egg retrieval cycle has about a 7 in 10 chance of a live birth. If she has a second cycle and freezes another 10 eggs, her chance of having a live birth jumps to 9 in 10. With 30 eggs, the chance of success rises to 97%.

The number of eggs that can be retrieved in a given cycle varies, Fox said, noting that some women, mainly those 35 or younger, might produce as many as 20 in one try.

"As a general indication of what to expect from oocyte freezing, I think this is an advancement," Karin Hammarberg, an Australian researcher who coauthored a paper last month in Human Reproduction about the reproductive experiences of healthy women who opt to freeze their eggs, told me in an email. However, said Hammarberg, a registered nurse and senior research fellow at the Monash University public health school in Melbourne, success rates might not be the same at fertility clinics other than the Brigham's or in women who smoke, are obese or have some other condition that could reduce their fertility.

Said Fox, who hopes to develop an app or a web-based tool based on her research, "I sense that this model we've created will really help physicians and patients make the most informed decisions they can."

I’ve been a journalist ever since I edited my elementary school newspaper in Wheeling, W.Va. My father was an ob-gyn, which helps explain why I gravitated toward covering health and medicine, with a special interest in women’s health. As a freelance writer, I’ve written for...